Method of recording and/or reproducing data with respect to a multi-layer information storage medium having optimal power control areas

ABSTRACT

An information storage medium having a plurality of information storage layers, each of which includes an optimal power control (OPC) area for obtaining an optimal recording condition, wherein OPC areas in odd-numbered and even-numbered information storage layers are disposed not to face each other and not to contact each other, or partially overlap each other and lock out use of the overlapped portion. Therefore, when an OPC area of one information storage layer performs OPC, this OPC does not affect another information storage layer.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. patentapplication Ser. No. 11/204,180, filed Aug. 16, 2005, currently pending,which is a continuation application of U.S. patent application Ser. No.10/875,793, filed Jun. 25, 2004, currently pending, which claims thebenefit of Korean Patent Application No. 2003-42996, filed on Jun. 28,2003 in the Korean Intellectual Property Office, the disclosures ofwhich are incorporated herein in their entirety by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to recordable information storage media,and more particularly, to an information storage medium which minimizesan influence of optimal power control (OPC) process executed in an OPCarea included in each of information storage layers upon otherinformation storage layers of the information storage medium.

2. Description of the Related Art

General information storage media are widely used as informationrecording media of optical pickup apparatuses for recording/reproducingdata in a non-contact way. Optical disks are used as the informationstorage medium and classified as compact disks (CDs) or digitalversatile disks (DVDs) according to their information storage capacity.Examples of recordable, erasable, and reproducible optical disks are 650MB CD-R, CD-RW, 4.7 GB DVD+RW, and the like. Furthermore, highdensity-DVDs (HD-DVDs) having a recording capacity of 25 GB or greaterare under development.

As described above, information storage media have been developed tohave a greater recording capacity. The recording capacity of aninformation storage medium can be increased in two representative waysof: 1) reducing the wavelength of a recording beam emitted from a lightsource; and 2) increasing the numerical aperture of an objective lens.In addition, there is a way of forming a plurality of informationstorage layers.

FIGS. 1A and 1B schematically illustrate a dual-layered informationstorage medium having first and second information storage layers L0 andL1. The first and second information storage layers L0 and L1 includefirst and second optimal power control (OPC) areas 111 and 121,respectively, for obtaining optimal writing power and first and seconddefect management area (DMAs) 115 and 125, respectively. The first andsecond OPC areas 111 and 121 face each other (i.e, are disposed at acommon radius relative to an inner or outer boundary of the informationstorage medium).

Data is recorded in the first and second OPC areas 111 and 121 usingvarious levels of writing power to find the optimum writing power.Hence, data may be recorded with a higher level of power than theoptimum writing power. Table 1 shows variations in the jittercharacteristics of each of the first and second information storagelayers L0 and L1 when data is recorded in the OPC areas 111 and 121 withdifferent levels of writing power.

TABLE 1 Writing power about 20% higher than normal writing Normalwriting power power L0 Writing Un- Writing Written Writing Writtenwritten L1 Unwritten Writing Written Writing Written Writing Jitter L05.9% 6.0% 5.8% 5.9%-> 6.4% L1 6.3% 6.2% 6.3% 6.2%-> 6.3% Writing L0 6.46.3 6.3 7.5 6.4 Power L1 6.0 6.0 6.2 6.0 7.2

According to Table 1, if data is recorded with normal writing power, thejitter characteristics of the first or second information storage layerL0 or L1 keep constant. On the other hand, if data is recorded withwriting power about 20% higher than the normal writing power, the jittercharacteristics of the OPC area of the first or second informationstorage layer L0 or L1 in which data has already been recorded aredegraded. If data is recorded on one of the first and second informationstorage layers L0 and L1 with writing power more than 20% higher thanthe normal writing power, it can be expected that the jittercharacteristics of the other information storage layer may be furtherdegraded.

Hence, if the first and second OPC areas 111 and 121 of the first andsecond information storage layers L0 and L1 exist within an equal radiusas shown in FIGS. 1A and 1B, one of them may not be usable.

The recording status of one of the first and second OPC areas 111 and121 may affect the recording characteristics of the other OPC area. Forexample, as shown in FIG. 1B, if data has been recorded on a part 111 aof the first OPC area 111 and no data has been recorded on the residualarea 111 b thereof, the recording property of a part of the second OPCarea 121 which corresponds to the occupied part 111 a of the first OPCarea 111 is different from that of a part of the second OPC area 121which corresponds to the unoccupied part 111 b of the first OPC area111. In other words, since the transmittance of a laser with respect tothe occupied part 111 a of the first OPC area 111 is different from thetransmittance of a laser with respect to the unoccupied part 111 bthereof, the recording property of the second OPC area 121 may beirregular over the area.

As described above, if the first and second OPC areas are disposedwithin an equal radius, they may not properly function.

SUMMARY OF THE INVENTION

According to an aspect of the present invention, an information storagemedium which minimizes an influence of optimal power control (OPC)executed in an OPC area included in each of a plurality of informationstorage layers upon other information storage layers is provided.

According to an aspect of the present invention, there is provided aninformation storage medium having a plurality of information storagelayers, each of which includes an optimal power control area forobtaining an optimal recording condition, wherein optimal power controlareas in odd-numbered and even-numbered information storage layers aredisposed within different radiuses of the information storage medium andreserved areas are disposed adjacent to each of the OPC areas.

According to another aspect of the present invention, there is providedan information storage medium having a plurality of information storagelayers, each of which includes an optimal power control area forobtaining an optimal recording condition, wherein optimal power controlareas in odd-numbered and even-numbered information storage layers aredisposed one on another such that each optimal power control area ispartially overlapped by another optimal power control area.

According to another aspect of the present invention, there is providedan information storage medium having a plurality of information storagelayers, each of which includes an optimal power control area forobtaining an optimal recording condition, wherein optimal power controlareas in odd-numbered and even-numbered information storage layersviewed from a direction in which light is incident upon the informationstorage medium are disposed within an identical radius of theinformation storage medium, and directions in which the optimal powercontrol areas in odd-numbered and even-numbered information storagelayers are used are opposite.

Additional aspects and/or advantages of the invention will be set forthin part in the description which follows and, in part, will be obviousfrom the description, or may be learned by practice of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and/or other aspects and advantages of the present inventionwill become more apparent by describing in detail exemplary embodimentsthereof with reference to the attached drawings of which:

FIGS. 1A and 1B are views illustrating an influence of an OPC area uponan area other than the OPC area in a conventional dual-layeredinformation storage medium;

FIG. 2 illustrates a layout of a data area of a dual-layered informationstorage medium according to an embodiment of the present invention;

FIGS. 3A and 3B illustrate a case where data is recorded in first andsecond information storage layers of the information storage medium ofFIG. 2 in identical directions;

FIGS. 4A and 4B illustrate a case where data is recorded in the firstand second information storage layers of the information storage mediumof FIG. 2 in different directions;

FIGS. 5A and 5B illustrate a layout of a data area of a dual-layeredinformation storage medium according to another embodiment of thepresent invention;

FIG. 6 illustrates a layout of a data area of a dual-layered informationstorage medium according to another embodiment of the present invention;

FIG. 7 illustrates a layout of a data area of a dual-layered informationstorage medium according to another embodiment of the present invention;

FIG. 8 illustrates a layout of a data area of a dual-layered informationstorage medium according to a further embodiment of the presentinvention;

FIG. 9 illustrates a layout of a data area of a dual-layered informationstorage medium according to another embodiment of the present invention;

FIG. 10 is a block diagram of an apparatus for recording/reproducinginformation to/from the information storage medium of FIGS. 2-9according to an embodiment of the present invention; and

FIG. 11 is a more detailed block diagram of the recording and/orreproducing apparatus of FIG. 10.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Reference will now be made in detail to the embodiments of the presentinvention, examples of which are illustrated in the accompanyingdrawings, wherein like reference numerals refer to the like elementsthroughout. The embodiments are described below to explain the presentinvention by referring to the figures.

Referring to FIG. 2, an information storage medium according to anembodiment of the present invention includes at least two informationstorage layers L0, L1, each of which includes an optimal power control(OPC) area for obtaining optimal power. The OPC areas 211, 223 of theinformation storage layers are disposed within different radii such thatthe OPC areas 211, 223 do not face each other. Each of the informationstorage layers L0, L1 may include a reserved area 213, 221, and a defectmanagement area (DMA) 215, 225. Although not shown, each of theinformation storage layers may include a map area adjacent to the OPCarea.

The information storage medium shown in FIG. 2 includes the first andsecond information storage layers L0 and L1. The first informationstorage layer L0 includes a first OPC area 211, a first reserved area213, and a first defect management area (DMA) 215, and the secondinformation storage layer L1 includes a second reserved area 221, asecond OPC area 223, and a second DMA 225.

The first and second OPC areas 211 and 223 in the information storagelayers L0 and L1 are disposed within different radii of the informationstorage medium such that contact with each other is avoided. Morespecifically, the second reserved area 221 is disposed in an area of thesecond information storage layer L1 opposite to the first OPC area 211of the first information storage layer L0, and the first reserved area213 is disposed in an area of the first information storage layer L0opposite to the second OPC area 223 of the second information storagelayer L1.

The first and second DMAs 215 and 225 of the first and secondinformation storage layers L0 and L1, respectively, are preferablydisposed within an identical radius of the information storage medium.

In such a structure as shown in FIG. 2, an address of a used part of anOPC area 211, 223 in each of the information storage layers L0, L1 isrecorded at a predetermined location of a lead-in area.

FIGS. 3A and 3B illustrate a case where data is recorded in the firstand second information storage layers L0 and L1 of the informationstorage medium of FIG. 2 in identical directions, that is, a case whereboth the first and second OPC areas 211 and 223 are accessed inidentical sequences. In FIG. 3A, data is recorded in both the first andsecond information storage layers L0 and L1 in an identical directionfrom an inner boundary to an outer boundary of the information storagemedium of FIG. 2 regardless of a track spiral direction of theinformation storage medium. Hence, data is recorded in both the OPCareas 211 and 223 of the information storage layers L0 and L1 in theidentical direction from the inner boundary to the outer boundary of theinformation storage medium of FIG. 2.

In FIG. 3B, data is recorded in both the first and second informationstorage layers L0 and L1 in an identical direction from the outerboundary to the inner boundary of the information storage medium of FIG.2 regardless of the track spiral direction of the information storagemedium. Hence, data is recorded in both the first and second OPC areas211 and 223 of the information storage layers L0 and L1 in the identicaldirection from the outer boundary to the inner boundary of theinformation storage medium of FIG. 2.

In FIGS. 3A and 3B, it is understood that the order of the OPC area 211,223 and the reserved area arranged in each of the first and secondinformation storage layers L0 and L1 may be inverted.

FIGS. 4A and 4B illustrate a case where data is recorded in the firstand second information storage layers L0 and L1 of the informationstorage medium of FIG. 2 in different directions, that is, a case whereboth the OPC areas 211 and 223 are accessed in different sequences. InFIG. 4A, regardless of the track spiral direction of the informationstorage medium of FIG. 2, data is recorded in the first informationstorage layer L0 from the inner boundary to the outer boundary of theinformation storage medium of FIG. 2, and data is recorded in the secondinformation storage layer L1 from the outer boundary to the innerboundary of the information storage medium. Hence, data is recorded inthe OPC area 211 of the first information storage layer L0 from theinner boundary to the outer boundary of the information storage mediumof FIG. 2, and data is recorded in the second OPC area 223 of the secondinformation storage layer L1 from the outer boundary to the innerboundary of the information storage medium of FIG. 2.

In FIG. 4B, regardless of the track spiral direction of the informationstorage medium of FIG. 2, data is recorded in the first informationstorage layer L0 from the outer boundary to the inner boundary of theinformation storage medium, and data is recorded in the secondinformation storage layer L1 from the inner boundary to the outerboundary of the information storage medium. Hence, data is recorded inthe first OPC area 211 of the first information storage layers L0 fromthe outer boundary to the inner boundary of the information storagemedium of FIG. 2, and data is recorded in the second OPC area 223 of thesecond information storage layers L1 from the inner boundary to theouter boundary of the information storage medium of FIG. 2.

In FIGS. 4A and 4B, it is understood that the order of the OPC area andthe reserved area arranged in each of the first and second informationstorage layers L0 and L1 may be inverted.

FIGS. 5A and 5B illustrate an information storage medium according toanother embodiment of the present invention, in which a location of anOPC area in an information storage layer is partially overlapped by thatin another information storage layer. In this aspect of the informationstorage medium, the size of a reserved area 513, 531, 521, 543 having alow probability of being used is preferably, but not necessarily,smaller than that of the OPC area 511, 533, 523, 541. When the locationsof the OPC areas 533, 541 in different information storage layers L0, L1are partially overlapped by each other, an address of a used part of theOPC area 511 a, 533 a, 523 a, 541 a in each of the first and secondinformation storage layers L0 and L1 is recorded in a lead-in area orthe like to prevent the OPC areas with the identical radius in thedifferent information storage layers from being used together to recorddata. An OPC area address can be recorded in various forms, for example,in the form of a bitmap.

In FIG. 5A, data is recorded in a first information storage layer L0from the inner boundary to the outer boundary of the information storagemedium, and data is recorded in a second information storage layer L1from the outer boundary to the inner boundary of the information storagemedium. The first information storage layer L0 includes a first OPC area511, a first reserved area 513, and a first DMA 515, and the secondinformation storage layer L1 includes a second OPC area 523, a secondreserved area 521, and a second DMA 525.

The first and second OPC areas 511 and 523 of the first and secondinformation storage layers L0 and L1, respectively, are disposed withindifferent radii of the information storage medium to be partiallyoverlapped by each other. More specifically, the second reserved area521 and a second part 523 a of the second OPC area 523 of the secondinformation storage layer L1 are disposed opposite to the first OPC area511 of the first information storage layer L0, and a first part 511 a ofthe first OPC area 511 and the first reserved area 513 of the firstinformation storage layer L0 are disposed opposite to the second OPCarea 523 of the second information storage layer L1.

In FIG. 5B, data is recorded in a first information storage layer L0from the outer boundary to the inner boundary of the information storagemedium, and data is recorded in a second information storage layer L1from the inner boundary to the outer boundary of the information storagemedium. The first information storage layer L0 includes a first OPC area533, a first reserved area 531, and a first DMA 535, and the secondinformation storage layer L1 includes a second OPC area 541, a secondreserved area 543, and a second DMA 545.

The first and second OPC areas 533 and 541 of the first and secondinformation storage layers L0 and L1, respectively, are disposed withindifferent radii of the information storage medium to be partiallyoverlapped by each other. More specifically, a second part 541 a of thesecond OPC area 541 and the second reserved area 543 are disposedopposite to the first OPC area 533 of the first information storagelayer L0, and the first reserved area 531 and a first part 533 a of thefirst OPC area 533 are disposed opposite to the second OPC area 541 ofthe second information storage layer L1.

In such a structure as illustrated in FIGS. 5A and 5B, an address of aused part of an OPC area 511, 523, 533, 541 in each information storagelayers L0, L1 is recorded in a predetermined location of a lead-in area,for example, in a disk information area.

The size of an actually usable part of an OPC area 511, 523, 533, 541 ineach of the different information storage layers L0, L1 of aninformation storage medium as illustrated in FIGS. 5A and 5B variesdepending on a frequency of the use of each of the information storagelayers L0, L1 and information about an address of a used part of the OPCarea 511, 523, 533, 541.

FIG. 6 illustrates an information storage medium according to anotherembodiment of the present invention. In the first and second informationstorage layers L0 and L1 of FIG. 6, a map area 612, 622 for recording anaddress of a used part of an OPC area is disposed adjacent to each ofthe OPC areas 611, 623. When such a map area is disposed adjacent to anOPC area in each information storage layer as described above, a usablepart of the OPC area can be rapidly identified before the OPC isperformed in each information storage layer. Thus, a time required toperform the OPC can be shortened.

In FIG. 6, the first information storage layer L0 includes a first OPCarea 611, a first map area 612, a first reserved area 613, and a firstDMA 615, and the second information storage layer L1 includes a secondreserved area 621, a second map area 622, a second OPC area 623, and asecond DMA 625. The first and second map areas 612 and 622 are disposedwithin an identical radius of the information storage medium, andlikewise for the first and second DMAs 615 and 625 are disposed on thesame radius.

In the information storage medium of FIG. 6, directions in which data isrecorded in the OPC areas 611 and 623 of the information storage layersL0 and L1 are either in the same direction as illustrated in FIGS. 3Aand 3B or in different directions as illustrated in FIGS. 4A and 4B.

FIG. 7 illustrates an information storage medium according to yetanother embodiment of the present invention. In FIG. 7, first and secondOPC areas 711 and 721 of first and second information storage layers L0and L1 are disposed within an identical radius of the informationstorage medium, and directions in which data is recorded in the firstand second information storage layers L0 and L1 are set to be different.The first and second information storage layers L0 and L1 also includefirst and second DMAs 715 and 725, respectively. In FIG. 7, directionsof data recording in the first and second information storage layers L0and L1 are from an inner boundary to an outer boundary of theinformation storage medium and from the outer boundary to the innerboundary, respectively. However, the directions of data recording in thefirst and second information storage layers L0 and L1 may be from theouter boundary to the inner boundary of the information storage mediumand from the inner boundary to the outer boundary, respectively.

When OPC areas 711, 721 in information storage layers L0, L1 aredisposed within an identical radius of an information storage medium,addresses of used parts of the OPC areas 711, 721 in the informationstorage layers L0, L1 are recorded in a lead-in area or the like toprevent OPC areas 711, 721 of the identical radius in the informationstorage layers from being used together upon data recording.Accordingly, if directions in which data is recorded in the first andsecond OPC areas 711 and 721 are set to be different even though thefirst and second OPC areas 711 and 721 are disposed within an identicalradius of the information storage medium of FIG. 7, a part of each ofthe OPC areas 711 and 721 ranging up to an address ‘a’ can be used upondata recording. The address ‘a’ denotes an address where data recordingin the first OPC area 711 coincides with data recording in the secondOPC area 721.

The size of an actually usable part of an OPC area 711, 721 in eachinformation storage layer L0, L1 of an information storage medium asillustrated in FIG. 7 varies depending on a frequency of the use of eachof the information storage layers L0, L1 and information about anaddress of a used part of the OPC area 711, 721. Such a structure can beusefully applied to a small mobile information storage medium in which alarge capacity of data is recorded.

FIG. 8 illustrates an information storage medium according to anotherembodiment of the present invention. Considering the fact thatcharacteristics of data recording in inner and outer boundaries of aninformation storage medium may be different, OPC areas are disposed inat least one of the lead-in and lead-out areas 810 and 830 of theinformation storage medium of FIG. 8, which are disposed on both sidesof a data area 820. In first and second information storage layers L0and L1 of FIG. 8, first and second OPC areas 811 and 817 of the lead-inarea 810 and third and forth OPC areas 831 and 837 of the lead-out area830 may be disposed using one of the arrangements illustrated in FIGS. 2through 6 incorporating the first and third reserved areas 813 and 833and the data area 821 of the first information storage layer L0, and thesecond and third reserved areas 817, 835 of the second informationstorage layer L1.

FIG. 9 illustrates an information storage medium according to anotherembodiment of the present invention. As illustrated in FIG. 7, first andsecond OPC areas 911 and 913 in which data is recorded in oppositedirections are disposed in a lead-in area 910 within an identical radiusof the information storage medium, and third and forth OPC areas 931 and933 in which data is recorded in opposite directions are disposed in alead-out area 930 within an identical radius of the information storagemedium. The lead-in area 910 and the lead-out area 930 are disposed onopposite sides of a data area 920, which includes first and second dataareas 921 and 923 of the first and second information storage layers L0and L1, respectively.

FIG. 10 is a block diagram of an optical recording and/or reproducingapparatus according to an embodiment of the present invention in whichthe information storage media of FIGS. 2-9 are implemented. Referring toFIG. 10, the recording and/or reproducing apparatus includes awriting/reading unit 1000 and a control unit 1002. The writing/readingunit 1000 reads from and writes to the information storage medium 130according to commands from the control unit 1002. Here, the informationstorage medium 130 includes several embodiments shown in FIGS. 2 through9 and the control unit 1002 controls data writing/reading operations ofthe writing/reading unit 1000 so as to minimize interference between afirst optimal power control area in a first information storage layer L0and a second optimal power control area in a second information storagelayer L1 of the information storage medium 130.

Referring to FIG. 10, according to the control of the control unit 1002,the writing/reading unit 1000 records data on a disc 130, which is aninformation storage medium according to embodiments of the presentinvention, and reads out data in order to reproduce recorded data. Thecontrol unit 1002 controls the writing/reading unit 1000 so that thewriting/reading unit 1000 records data in predetermined recording unitblocks, or processes data read by the writing/reading unit 1000 andobtains valid data. Reproducing refers to obtaining valid data byperforming error correction for the read data, and is performed inpredetermined units. The units for performing reproduction are referredto as reproducing unit blocks. A reproducing unit block corresponds toat least one recording unit block.

FIG. 11 is a more detailed block diagram of the optical recording and/orreproducing apparatus of FIG. 10. Referring to FIG. 11, the informationstorage medium 130 is loaded in the writing/reading unit 1000. Therecording and/or reproducing apparatus further includes an opticalpickup 1100 that reads from and writes to the information storage medium130. The control unit 1002 includes a PC I/F 1101, a DSP 1102, an RF AMP1103, a servo 1104, and a system controller 1105, all of whichconstitute the control unit 1002 of FIG. 10.

In the data recording operation, the PC I/F 1101 receives a recordingcommand with data to be recorded from a host. The DSP 1102 addsadditional data such as a parity for error correction of the datareceived from the PC I/F 1101 and performs error correction and checking(ECC) encoding to generate an ECC block, which is an error correctionblock, and modulates the ECC block according to a predetermined method.The RF AMP 1103 converts the data output from the DSP 1102 into an RFsignal. The pickup 1100 records the RF signal output from the RF AMP1103 on the disc 130. The servo 1104 receives a command required forservo control from the system controller 1105 and servo-controls thepickup 1100.

In the data reproducing operation, the PC I/F 1101 receives areproduction command from a host (not shown). The system controller 1105performs the initialization required for reproduction. The pickup 1100emits a laser beam onto the disc 130, obtains an optical signal byreceiving a reflected beam from the disc 130, and outputs the opticalsignal. The RF AMP 1103 converts the optical signal output from thepickup 1100 into an RF signal and provides modulated data obtained fromthe RF signal to the DSP 1102 while providing a servo signal for controlof the pickup 1100 obtained from the RF signal to the servo 1104. TheDSP 1102 demodulates the modulated data, performs error correction andoutputs the resulting data. Meanwhile, the servo 1104 performs servocontrol of the pickup 1100, by using the servo signal received from theRF AMP 1103 and a command required for servo control received from thesystem controller 1105. The PC I/F 1101 transfers the data received fromthe DSP 1102 to the host.

The aforementioned OPC area arrangements are applicable to allinformation storage media regardless of whether a track of eachinformation storage layer is spiraled from an inner boundary to an outerboundary or from the outer boundary to the inner boundary. Theaforementioned OPC area arrangements are also applicable to all of themulti-layered information storage media having a plurality ofinformation storage layers regardless of whether an information storagelayer to be reproduced first is either an information storage layerfarthest from or closest to a pickup. For example, the aspects of thepresent invention described above are applicable to CD-R, CD-RW, DVD+RW,HD-DVD, Bluray, and Advanced Optical Disc (AOD) type information storagemedia.

Although the OPC area arrangements have been described with regard to adual-layered information storage medium having two information storagelayers, they may be applied to information storage media having at leastthree information storage layers which are stacked one on another.

As described above, in an information storage medium having a pluralityof information storage layers, an OPC area of one information storagelayer may be located over an OPC area of another information storagelayer such as not to face each other according to an aspect of thepresent invention. Therefore, when an OPC area of one informationstorage layer performs OPC, this OPC does not affect another informationstorage layer.

Alternatively, the OPC area of one information storage layer may belocated over an OPC area of another information storage layer to bepartially overlapped by each other, and directions of the use of the OPCareas are set to be different according to an aspect of the presentinvention. Therefore, when the OPC area of one information storage layerperforms OPC, this OPC does not affect another information storagelayer.

Alternatively, the OPC area of one information storage layer may belocated over an OPC area of another information storage layer face eachother, and directions of the use of the OPC areas are set to bedifferent according to an aspect of the present invention. Therefore,when the OPC area of one information storage layer performs OPC, thisOPC does not affect another information storage layer.

Although a few embodiments of the present invention have been shown anddescribed, it would be appreciated by those skilled in the art thatchanges may be made in these embodiments without departing from theprinciples and spirit of the invention, the scope of which is defined inthe claims and their equivalents.

1. A method of recording and/or reproducing data with respect to aninformation storage medium, the information storage medium comprising afirst information storage layer comprising a first optimal power controlarea, a first reserved area, and a first defect management area, and asecond information storage layer comprising a second optimal powercontrol area, a second reserved area, and a second defect managementarea, the first optimal power control area of the first informationstorage layer being aligned with the second reserved area of the secondinformation storage layer, and the second optimal power control area ofthe second information storage layer being aligned with the firstreserved area of the first information storage layer, the recordingand/or reproducing method comprising: recording data on at least one ofthe first and second optimal power control areas; and determining anoptimal recording/reproducing power using the data read from the one offirst and second optimal power control areas.
 2. The method of claim 1,wherein: the first information storage layer includes a first map areastoring information about the first optimal power control area of thefirst information storage layer and which is disposed adjacent to thefirst optimal power control area, the second information storage layerincludes a second map area storing information about the second optimalpower control area of the second information storage layer and which isdisposed adjacent to the second optimal power control area, the firstinformation storage layer is adjacent to the second information storagelayer, and the first and second map areas are formed on an identicalradius of the information storage medium.
 3. The method of claim 1,wherein the information storage medium further comprises informationabout the first and second optimal power control areas of the first andsecond information storage layers recorded in a lead-in area wheredisk-related information is recorded.
 4. The method of claim 1, whereina direction in which the first optimal power control area of the firstinformation storage layer is used to store data is identical to adirection in which the second optimal power control area of the secondinformation storage layer is used to store data.
 5. The apparatus ofclaim 1, wherein a direction in which the first optimal power controlarea of the first information storage layer is used to store data isopposite to a direction in which the second optimal power control areaof the second information storage layer is used to store data.
 6. Themethod of claim 4, wherein each of the directions in which the first andsecond optimal power control areas of the first and second informationstorage layers are used is one of a track spiral direction of each ofthe first and second information storage layers and a direction oppositeto the track spiral direction of each of the first and secondinformation storage layers.
 7. The method of claim 5, wherein each ofthe directions in which the first and second optimal power control areasof the first and second information storage layers are used is one of atrack spiral direction of each of the first and second informationstorage layers and a direction opposite to the track spiral direction.8. The method of claim 4, wherein the first and second optimal powercontrol areas are formed in at least one of a lead-in area and alead-out area.
 9. The method of claim 5, wherein the first and secondoptimal power control areas are formed in at least one of a lead-in areaand a lead-out area.
 10. A method of recording and/or reproducing datawith respect an information storage medium, the information storagemedium comprising a first information storage layer comprising a firstoptimal power control area, a first reserved area, and a first defectmanagement area, and a second information storage layer comprising asecond optimal power control area, a second reserved area, and a seconddefect management area, the first optimal power control area of thefirst information storage layer being aligned with the second reservedarea of the second information storage layer, the second optimal powercontrol area of the second information storage layer being aligned withthe first reserved area of the first information storage layer, and thefirst defect management area of the first information storage layerbeing aligned with the second defect management area of the secondinformation storage layer, the recording and/or reproducing methodcomprising: recording data on at least one of the first and secondoptimal power control areas; and determining an optimalrecording/reproducing power using the data read from the one of thefirst and second optimal power control areas.
 11. The apparatus of claim10, wherein information about the first and second optimal power controlareas of the first and second information storage layers is recorded ina lead-in area where disk-related information is recorded.
 12. Theapparatus of claim 10, wherein the first and second optimal powercontrol areas exist in at least one of a lead-in area and a lead-outarea.